The System Management Bus (often abbreviated as SMBus or SMB) is a relatively simple two-wire bus used for communication among various devices of a computer system. Examples of such devices which may communicate data over an SMBus include temperature sensors, lid switches and a rechargeable battery subsystem.
In the design and manufacturing of a computer system or other system which may utilize one or more SMBus devices, one approach has been to connect actual SMBus devices to the SMBus of a system being tested to ensure proper operation of the SMBus related functions. However, the actual SMBus devices may not be available for testing with the system being tested for a variety of reasons. Accordingly, another approach as depicted in FIG. 1, has been to connect a general purpose workstation 10 to the SMBus 12 of the system 14 being developed. A general purpose workstation such as the workstation 10 typically includes a monitor 18, keyboard 20, and a central processing unit (CPU) case 16 which usually houses a motherboard on which a microprocessor, the main memory, and other components are typically mounted. Additional components such as external storage, controllers for video display and sound, and peripheral devices are frequently attached to the motherboard via edge connectors and cables. However, it is increasingly common to mount integrated circuits for these and other peripheral devices onto the motherboard. In this example, the workstation 10 typically has an expansion card 30 carrying a suitable bus adapter (such as an I2C (Integrated Circuit Inter) compatible adapter) which permits the workstation 10 to be coupled to the SMBus 12 of the system 14 being tested.
The workstation 10 may be programmed with an application program typically loaded by the general operating system from magnetic or optical storage to enable the workstation 10 to emulate a bus device. The program may have a learning mode by which bus signals generated by other devices on the bus 12 are recorded by the workstation 10. In a subsequent emulation mode, stored bus signals may be retransmitted by the workstation 10 over the bus 12 in response to received signals, thereby emulating an actual bus device.